The Malaysian developer IJM Corporation bought the long lease on the historic Grade II-listed building earlier this year, with planning consent already secured for a major overhaul.
Ardmore was previously lined up to deliver the job prior to the ownership transfer, but IJM is now understood to have decided to self-manage construction.
It will use JRL, which it bought a 50% stake in earlier this year, to deliver the project.
The project marks one of the most ambitious City refurbishments ever approved by the Corporation of London, increasing the building’s size by 26% from 300,000 sq ft to 378,000 sq ft via a two-storey rooftop extension.
Work is starting immediately with completion due within 36 months.
Designed by architect Carmody Groarke, the scheme includes major sustainability upgrades targeting BREEAM ‘Outstanding’, WELL ‘Platinum’, NABERS 4 Star and WiredScore ‘Platinum’ ratings, alongside net-zero operational carbon.